Coating machine



Sept. 18, 1934. c. E. HOOD coATINcmomma Filed Oct. 1. 1929 Patented Sept. 18, 1934 PATENT OFFICE COATING MACHINE Charles E. Hood, Lynn, Mass., assignor to United Shoe Machinery Corporation, Paterson, N. 3.,

a corporation of New Application October 1,

8 Claims.

This invention relates to coating machines and is herein illustrated as embodied in a machine for applying liquid to one surface of a shoe sole.

In the manufacture of shoes of the so-called cement-process type in which the sole of the shoe is attached to the overlasted upper of the shoe by means of cement or other adhesive, it is customary to apply a coating of cement to the marginal portions of the attaching surface of the shoe sole some substantial period of time before the sole is actually secured to the shoe, as well as to apply cement to the overlasted marginal portion of the upper on the bottom of the shoe. The cement is allowed to dry on both sole and shoe before the 'shoe is brought to the sole attaching machine where the sole is pressed against the shoe and caused to adhere thereto. In many cases the cement to be utilized is a pyroxylin cement which dries relatively quickly and which, at the same time, may be easily softened or revived by the application of any one of a large number of solvents such as acetone, amyl acetate, ethyl alcohol, benzol and the like. These solvents while they attack the cement and soften it very quickly are almost universally very volatile liquids. It is well understood that the rate of action of the solvent may be slowed down by the introduction of pyroxylin in the solvent, yet it is equally well understood that such a slowing down of the action of the solvent also slows down the time required to dry out the cement and is, therefore, objec tionable because of the increased time during which mechanical apparatus for clamping the sole upon the shoe must be retained in position. The longer the time required for drying out the cement the greater tlie amount of apparatus which must be employed and hence the greater the investment required.

Although it will be understood that the practic varies considerably between different shoe manufacturers, the common practice has been for the manufacturer to utilize a solvent of moderate drying speed and to apply this solvent to the sole by means of a brush which has to be dipped in the solvent two or three times before completely coating the cement on the sole. Furthermore, it has been previously intimated that the action of the solvent upon the cement is rapid and the result of this is to make it diflicult to apply the solvent evenly to the sole because, if a solvent of even moderate speed is employed the portions of the sole first coated are likely to become dried out again before the portions coated last have been finished andthe sole and shoe are brought together.

Jersey 1929, Serial No. 396,554

In view of the foregoing, an object of the present invention is to provide a machine for applying liquid, such as a solvent, to a cemented surface of a piece of work such as the attaching face of a shoe sole which machine will be organized to cause the liquid to be applied quickly and evenly to the desired work surface without coating the opposite surface of the work.

In applying solvent to the previously coated attaching surface of a shoe sole it is desirable to treat the whole cemented surface substantially simultaneously as by partial immersion without allowing the liquid to be applied to the tread face of the sole, partly because it is not desired'to smear or stain the tread surface of the sole, but also to avoid waste of the rather expensive solvent material employed. The novel method of preparing soles for permanent attachment to-shoes by means of cement and involving the coating with solvent of the whole of the cemented area of the sole substantially simultanecuslyis not claimed herein, since it forms the subject-matter of a divisional application, Serial No. 692,487, filed October 6, .1933.

As herein illustrated, a machine is provided having a receptacle and depressible work supporting grid, together with means for maintaining the level of the liquid in the receptacle at a predetermined point. The illustrated machine is also provided with novel means for resiliently supporting the grid and a coacting presser member, and has means for limiting the movement of the grid with respect to the level of the liquid so that its sole supporting surface may be depressed only enough to apply solvent to the cement coating upon the under or attaching face of a sole positioned on the grid.

The volatile nature of the solvents employed increases the danger of the loss by evaporation. However, this danger is offset to a considerable extent in accordance with another feature of the invention by substantially enclosing the liquid receptacle and the work supporting grid and providing a lateral opening for the admission of pieces. of work well down the side of the receptacle so that a quantity of liquid vapor is held in the receptacle tending to prevent further losses through evaporation and itself working on the cement upon the sole in case the latter is allowed to stand in the machine either before or after its partial immersion.

Still other features of theinvention reside in an improved inverted supply container having novel control means adjustable to determine the level of the liquid and in an improved grid which is illustrated as constructed with intersecting bars, the edges of which are notched to avoid pumping and splashing the liquid.

In the drawing,

Fig. 1 is a vertical longitudinal section through the machine;

Fig. 2 is an end elevation of the machine with one side broken away and in section transversely through an operating rod;

Fig. 3 is a plan view of the machine with a cover removed; and l Fig. 4 is a fragmentary transverse section showing how the presser member moves a sole and the grid a definitely limited distance to bring the lower, here the attaching surface of the sole, just below the surface of the liquid.

In general the method may be carried out by the use of the machine which is operated to dip a piece of work into liquid with which the work is to be coated but this dipping movement is limited so that only one surface of a sole will be coated. Accordingly the machine provides a receptacle 10 for liquids in which the body of liquid is maintained at a predetermined level indicated by the dash line 12. In this receptacle there is mounted for up and down movement a work supporting member in the form of a grid 14 normally held in the position shown in Figs. 1 and 2 so that its upper surface is above the surface of the liquid but capable of being depressed to the position shown in Fig. 4 where its upper surface is just below the surface of the liquid. This grid 14 is constructed of a series of criss-crossed bars forming closed meshes, open at top and bottom, and notches 15 are provided in the upper edges while other notches 1'7 are provided in the lower edges of the bars. These upper notches allow air, which may be pocketed in the meshes, to escape between a piece of work and the top of the grid, and the two sets of notches allow a free flow of liquid contained within the meshes of the grid so as to avoid any pumping action which might splash liquid on the upper surface of the work.

The receptacle, as will be evident from an inspection of Fig. 2, has openings in its base constituting passageways or guideways 16 enlarged at 18 to form abutments and having their upper ends above the level of the liquid. In these guideways are a pair of upright rods 20 bolted to the upper ends of which is a presser plate 22 having a median rib 24 which terminates in outspreading lugs 26. The lugs 26 are cupped (Fig. 1) to receive the upper ends of springs 28 holding the presser plate 22 normally elevated. The lower ends of the springs are positioned in suitable recesses, not shown, formed in lateral ledges or shelves-30- (Fig. 3) one at either side of the receptacle into which the guideways 16, 18 open.- Operating means such as a treadle (not shown) may be secured by a treadle rod 32 to a cross bar 34 held upon the rods 20 by set screws 36. When the treadle is depressed the presser plate 22 is lowered. The grid 14 has a pair of oppositely extending flanges 40 which are apertured for the passage of the rods 20 and which rest upon the upper ends of short, stiff springs 42 received within and resting upon the abutments formed at the bottoms of the enlarged portions 18 of the guideways 16. These springs surround and are thereby held in position by the rods 20 and hold the grid with its upper surface normally just above the liquid level 12. Downward movement of the work-supporting grid 14 is definitely limited by contact of the grid with the bottom of the receptacle and by contact of the flanges 40 with the shelves 30 (Fig. 4) so that the top surface of the grid may be carried only just below the predetermined level of the liquid. This prevents the sole from being carried deep enough into the solvent to coat its tread surface.

In view of the volatile nature of the liquid to be employed the operating parts of the machine are substantially enclosed by providing a cover 44 for the receptacle 10 thereby reducing the loss by evaporation'and maintaining afog of solvent vapor in the machine. An inlet opening 46 of limited size in the end of the receptacle l0 and about as wide as the soles to be coated is positioned well below the top cover and above the liquid level, adjacent to and substantially opposite to the space between the presser member 22 and the work supporting grid 14. This allows a piece of work such as a shoe sole 48 to be laid upon the grid 14 before the presser is brought down and, without interfering with easy use of the machine, substantially reduces the evaporation of the liquid in the receptacle and aifords a pocket to maintain therein a cloud of vapor which assists in the cement softening action of the machine. The novel method of securing together a shoe sole and a shoe which involves the retention of the sole in a cloud of vapor such as is formed in this machine is not claimed herein, however, as it forms the subject-matter of an application of Max W. Tetlow, Serial No. 457,189, filed May 29, 1930.

As herein shown, liquid is supplied to the receptacle 10 and maintained at the level indicated by the line 12 by means of an inverted, air-tight can 50 having a threaded neck 52. Surrounding this neck and adjustably positioned thereon is a collar 54 which supports the can on the receptacle so that by turning the can with respect to the collar, the vertical'relation of an outlet opening 56 at the bottom of the neck of the can with respect to the receptacle 10 may be adjusted and predetermined. This relation will determine the level of the solvent in the receptacle. To facilitate the application of the supply can 50 to the receptacle without spilling the contents, said can is provided with a pivoted closure 58 having an opening 60 and held tightly against the end of the neck 52 by a spring 62. The can may be inverted and positioned with the collar 54 resting upon a ledge provided by an extension 64 of the re ceptacle 10 with the closure 58 turned to such position that the opening 60 therein is not in register with the opening 56. After the can has been positioned upon the extension 64 of the receptacle a sliding plunger 66 may be pushed into engagement with a notch in the edge of the closure 58 to hold the latter against rotation and the can rotated to bring the openings 56 and 60 into register with one another. When removing a partly empty can from the receptacle, the operation is reversed and spilling of the liquid avoided. It should be noted that the plunger 66 is slidablymounted in a block 68 secured to the extension 64 and is provided with a knurled handle '70 so that it may be pulled back out of engagement with the closure 58 in case it is desired to rotate the can 50 with respect to the shaped flanges (not shown) along the sides of the extension 64 of the receptacle.

In mounting the machine upon a bench 81 a rigid plate 74 is preferably provided which is screwed to the surface of the bench and which furnishes a smooth surface to support the machine. The machine has a leg '76 at one end and a pair of adjustable supports 78 at the other end which are threaded into the bottom of the receptacle 10 and are held in adjusted position therein by nuts 80. In setting up the machine the liquid may be brought substantially to the desired level 12 and the machine tilted by adjusting the supports '78 to bring the surface of the liquid into substantially parallel relation with the top of the grid 14. It will be noted that the bench 81 is apertured at 82 to provide for the passage of the operating rods 20, and at 84 to allow for drawing ofl the solvent through a petcock 86 at the close of operations or when it becomes necessary to clean out the machine.

In the use of the device the receptacle 10 is supplied with liquid from the can 50 which is brought to the desired level 12 by rotating said can as described so that the normally unobstructed surface of the upper surface of the liquid is just above the surface of the grid id in its depressed position. A sole 48, which in some instances will be substantially flat and will in other cases be molded as herein illustrated in dotted lines, is then laid upon the grid 14. After this the treadle is operated to bring the presser 22 against the upper or tread surface of the sole to flatten the sole out upon the grid 14 and then to depress the grid into the exposed surface of the open bath of liquid to bring the sole 48 and the grid. 1% to the position illustrated in Fig. i where the lower or attaching surface of the sole is in direct contact with the body of liquid just below the level 12 thereof and is immersed therein. Pressure upon the treadle is then released allowing the springs 42 and 28 to restore the operating parts to the position illustrated in Fig. l whereupon the sole may be removed from the machine by taking hold of the projecting heel endof the sole which usually is not coated with adhesive and hence need not be coated with solvent.

As the sole 48 is held against the upper surface of the grid by the presser member 22 air is likely to become imprisoned in those meshes of the grid which are closed at the top by the sole. This air is allowed to escape, however, through the notches of the grid bars as the grid is depressed so that the liquid will flow freely into all meshes of the grid and coat the under surface of the sole. It should be noted that certain of the meshes of the grid are not completely covered by the sole but there can be no pumping action through these partially closed meshes upon depression of the grid.

Having thus described my invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:-

1. In a coating machine, a receptacle for liquid having means for maintaining the level of the liquid in the receptacle at a predetermined point, said receptacle being provided with recesses the bottoms of which form abutments within the receptacle out of contact with the liquid, a work support, springs within the receptacle resting on said abutments carrying said work support to allow movement of the work support from a position where its upper surface is above the surface of the liquid to a position slightly below the surface of the liquid, the receptacle having surfaces adjacent to the upper edges of the recesses, the work support having surfaces adapted to contact with said surfaces on the receptacle to limit downward movement of the work support, and means for pressing against the upper surface of a piece of work on the support thereby to depress the work and said work support until the lower surface of the work has been brought into contact with the surface of the liquid.

2. In a machine for applying solvent to a cement coating on the attaching surface of a sole, a substantially enclosed receptacle having a de pressible sole supporting grid with its upper surface normally above the level of the surface of the liquid, said receptacle having a sole admitting opening in the end of the receptacle with a width corresponding to thewidth of soles to be coated, the upper edge of said opening being substantially below the top of the receptacle whereby liquid vapors are held within the receptacle and the bottom edge of the opening being above the level of the liquid and adjacent to the surface of said depressible grid.

3. In a coating machine, a receptacle for liquid having openings in its base communicating with vertical passageways the upper ends of which are above the level of the liquid in the receptacle, operator-controlled rods extending through said passageways to the interior of the receptacle, a depressible, perforated work support slidably guided on said rods, springs surrounding said rods yieldably to support said work support above the liquid, and a work pressing member fixed on said rods within the receptacle and positioned normally above the work support and movable into contact with the work to depress the work support.

4. In a coating machine a receptacle for liquid having a. depressible work supporting member, means for maintaining a supply of liquid at a predetermined level with respect to said work supporting member, said means comprising an inverted container, having a valve at its outlet and a screw collar to support the same on said receptacle, and withdrawable means mounted for engagement with said valve in one position in such a manner that the valve may be opened by rotation of the container and, after said means 125 has been withdrawn, the container may be rotated to adjust the level of the liquid in the receptacle without disturbing the position of the valve.

5. In a coating machine, a container for liq- 113d uid having a depressible grid, means for supplying liquid to said receptacle constructed and arranged to maintain the level of the liquid below the surface of the grid, said supply means comprising an inverted container having a rotatable valve 135 to close its outlet opening, said container also having a screw collar to support the container on the receptacle, and a slidable plunger in the receptacle adapted to be brought into engagement with the valve to hold said valve against Mil rotation when it is desired to open or close the valve, said plunger being arranged for movement out of operative engagement with the valve whereby the container may be rotated with I respect to the collar without disturbing the posi- 145 tion of the valve.

6. In a coating machine, a receptacle, means for maintaining a supply of liquid in said receptacle at a predetermined level, and a depressible grid normally positioned with its upper surface 150 liquid in receptacle below the upper surface of the grid, the upper edges of said bars having notches to permit the escape of air imprisoned between a piece of work and the liquid as said work and the grid are depressed to coat the lower surface of the work.

8. In a coating machine, a receptacle for liquid having a depressible grid therein formed from intersecting bars providing closed meshes, and means for maintaining the level of a supply of liquid in the receptacle below the upper surface of the grid, the bars of said grid being provided with relief openings to give freedom of movement to the liquid within the meshes of the grid as a piece of work is laid thereon and depressed with the grid.

CHARLES E. HOOD I 

